Method and apparatus for insulating a concrete wall

ABSTRACT

An insulated concrete wall system is disclosed in which the insulation is provided at the time the concrete wall is poured.

FIELD OF THE INVENTION

The present invention relates to poured concrete walls and, moreparticularly, to poured concrete walls including layers of thermalinsulation in which the insulation layers are secured to the concretewall at the time of pouring the concrete.

BACKGROUND

Concrete walls are commonly formed by pouring concrete between inner andouter forms and, after hardening, insulation materials may be added tothe concrete walls. In order to do so, frame members may be applied tothe concrete wall, such as by using pneumatic guns and concrete nails,and then the insulating material may be secured to the frame members.Alternatively, the insulation may be secured to the concrete wall byconcrete nails. Such multi-step assembly procedures are both timeconsuming and costly. Thus, there has long been a need for a system anda method whereby poured concrete walls may be formed and insulated atthe same time in one step, and particularly when both the inner andouter surfaces of the wall are to be insulated.

SUMMARY

The present invention provides an apparatus and method for securinginsulation layers in place while the concrete is poured betweenconventional forms, and for continuing to secure the insulation layersto the poured concrete wall after the forms have been removed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional,view of a poured concrete wall with a thermalinsulation layer secured to the inside surface of the wall;

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is an enlarged side-elevational view of one tie strip;

FIG. 4 is a top plan view of a wedge which is inserted into the tiestrip;

FIG. 5 is an enlarged, side elevational view of one form of supportelement for securing the insulation layer to the inner surface of theconcrete wall prior to, during, and after the concrete is poured;

FIG. 6 is a front plan view of the support element taken along line 6-6of FIG. 5;

FIG. 7 is a top plan view of the support element taken along line 7-7 ofFIG. 5;

FIG. 8 is an elevational view of a plurality of insulation panelssecured to the concrete wall by a plurality of support elements;

FIG. 9 is a perspective view of a block of insulation showing the cutsto form individual panels of insulation;

FIG. 10 is a side elevational view partly in cross-section of one stepof the insulation panel being installed;

FIG. 11 is a top cross-sectional view taken along view line 11-11 ofFIG. 10;

FIG. 12 is a side cross-sectional view of the panel during a second stepof the installation;

FIG. 13 is a side view (in section) showing insulation panels installedon both the inner and outer surfaces of the concrete wall before thewall is poured; and

FIG. 14 is a top cross-sectional view taken along view line 14-14.

DETAILED DESCRIPTION

Referring first to FIG. 1, numeral 10 designates a concrete wall whichhas been poured between first and second conventional forms 12 and 14.Forms 12, 14 are held together by metal strips or ties 16 as inconventional practice. However, as shown most clearly in FIG. 3, each ofties 16 includes a non-conventional slot 17 for a purpose hereinafterdescribed. Numeral 18 represents a conventional footing for supportingthe wall, and numeral 20 represents a plurality of conventionalreinforcing bars (“rebar”) which extend horizontally through the pouredconcrete to add strength to the wall.

The structure described thus far is typical of the manner of formingpoured concrete walls. After the concrete hardens, forms 12 and 14 areremoved and the concrete wall is complete. If insulation is to be added,frame members (not shown) must be secured to the wall, or sheets orrolls of insulation must be secured by pneumatic nailing guns. Aspreviously stated, this double-step procedure is both time consuming andcostly.

In the present invention, layers or panels of insulation 22 are securedin place before the concrete is poured between forms 12, 14. The meansfor securing the insulation in place during the pouring of the concretecomprise clips or wedges 23 and anchors or connectors 24. Clips orwedges 23, hereinafter wedges, are shown in detail in FIGS. 2 and 4.Each wedge comprises a molded piece of plastic, such as polypropylene,which is in the form of a double-ended V-shape with an open hole 26 inthe central region. As such, the wedges are flexible and resilient sothat they may be squeezed together in the center portion and insertedinto slots 17 of ties 16. Upon insertion, the center portions of thewedges expand such that grooves 28 lock in ties 16 and the wedges extendhorizontally. As shown most clearly in FIG. 2, approximately one-half ofeach wedge becomes embedded in the insulation panel, and the other halfbecomes embedded in the poured concrete. As a result, the insulationpanels become locked to fixed ties 16 so that the lightweight panelscannot “float” upwardly when the concrete is poured.

In addition to ties 16 and wedges 23, the present invention providesanchors or connectors 24 as shown in FIGS. 1 and 5-7. Preferably,connector elements 24 are in the form of a web portion 32 havingopenings 34 so that the poured concrete passes through and fills theopenings as-shown in FIG. 1. Thus, as the concrete hardens, connectors24 become bound and locked in the concrete.

As further shown most clearly in FIGS. 1 and 5-7, each connector 24includes an enlarged head portion 36 which extends laterally andvertically at a right angle relative to the web portion. Thus, when theweb portion of each connector passes through a slot 38 in the insulationpanel as shown in FIGS. 1 and 8, the panel is retained by head portion36 while the web portion is retained in and by the concrete. In thepreferred embodiment, it will be understood that the area of theinsulation surrounding slot 38 may be recessed or counter-sunk such thatthe exposed surface of the connector head is flush with the surface ofthe insulation. However, the thickness of the head portion is only inthe order of ¼ inch or less such that counter-sinking is not necessary.

Also in the preferred embodiment, stiffening side bars or ribs 37 may beadded as most clearly shown in FIGS. 5 and 7, and the stiffening ribsmay be provided with barbs 39 for engaging in insulation layer 22. Also,the upper and lower portions of connectors 24 may be provided with barbs41 which further engage and hold the insulation panel in place. Inaddition, in order to accommodate walls of either 6 or 8 inches inthickness, the horizontal length of connectors 24 may be manufactured ofa uniform 8 inch length, and with grooves 42 as shown in FIG. 5 near thetip of the connector such that the tip may be easily broken off for 6inch walls.

In the foregoing description, connectors 24 may be held in place duringthe concrete pouring by virtue of a tight frictional fit between the webportion 32 and slot 38 of the insulation panel and the frictionalengagement of barbs 39 and 41. However, a substantially greater securingof the connectors may be effected by providing one or more notches,grooves or hook portions 40 as shown in FIGS. 1 and 5. These hookportions may be engaged by rebar 20 so as to positively lock connectors24 in place before, during and after the concrete is poured.

Connectors 24 may be composed of any rigid material, but they arepreferably composed of molded plastic such as for example, polypropyleneor polyethylene. Such materials may be easily molded, are of low thermalconductivity and are low cost. Most importantly, they provide anexcellent medium for receiving nails, screws, staples or other meansthrough heads 36 for securing the later installation of additive wallmaterials such as plaster board, paneling or other finishing layers.

Insulation layer 22 may be composed of any commercially availablematerial of low thermal conductivity, but is preferably composed ofrigid panels of expanded or extruded polystyrene. In addition to thethermal insulation value of such panels, their inherent propertiesprovide a vapor barrier and their thermal properties are notdeteriorated by moisture.

The above-identified structure and method of forming the insulated wallhas proven to be very effective and efficient in insulating a concretewall. At the same time, it has been discovered that newly developedstructure and methods greatly expedite the entire process andsubstantially reduce the cost. For example, the previous method ofconstruction included forming 6 to 9 slots 38 in each single panel ofinsulation as shown in FIG. 8. These slots were of uniform width, andthey required “plunge-cutting” each slot with a mechanical cutter suchas a chain cutter similar to the well-known chain saw. With each plungeinto the single insulation panel an upper vertical portion of the slotwas cut, and then the cutter moved downwardly to complete the verticallength of the slot, after which it was withdrawn. Then the cutter, or asecond similar plunge-type cutter, was inserted into the single layer ofinsulation to cut the laterally extending slot portions 44 in order toreceive laterally extending barbs 39 of each web. While multiple slotscould be cut simultaneously by using a support structure for mounting anarray of cutters, the entire cutting process was slow and subject tofrequent mechanical breakdown of the cutters and/or the cutter supportstructure.

It has now been discovered that a large block of insulation, such asblock 46 in FIG. 9, may have vertical slots 38 cut in a single step bycutting through the entire block 46 with a hot wire cutter moving onlyvertically. The cutter need not move horizontally because it has beenfound that ribs 37, shown in FIG. 7, may be eliminated with the barbsextending latterally from the sides of the webs as shown in FIGS. 10 and12. It has also been found that the preferred method of cutting is toenter the block from one side, cut out a key 44 for added strength, andthen cut the vertical slot 38. Thereafter, block 46 may be sliced intoindividual layers 48 by a hot wire or other type cutter so as tomanufacture as many as 12 layers of insulation in only two steps. Thismethod both substantially increases the efficiency and lowers theproduction cost of each finished insulation panel.

In addition, it has also been discovered that the exterior surface ofthe wall may also be provided with a layer of insulation in combinationwith, or apart from, the description of the inner layer of insulation asjust described. Referring first to FIGS. 10 and 11 it will be understoodthat insulation panel 22 a has been prepared with slots 38, preferablyby the new method, and a plurality of webs 24 have been inserted intothe slots. However, it will be noted that the head portions 36 of webs24 are left protruding outwardly from the surface of the insulationpanel.

At this point in the assembly, a channel member 50, as shown in FIGS. 10and 11, is slid down over the heads of the webs as shown by an arrow Ain FIG. 10. Thereafter the channel and the webs are driven into thesurface of insulation panel 22 as shown in FIG. 12. In this regard itwill be understood that the vertical edges of the channel are sharpenough to cut into the insulation panel such as to be flush with thesurface of the panel. The panel is then slid horizontally between twoconventional wall forms 12, 14 as shown in FIG. 1 such that the taperedends of the webs extend into the space between the wall forms into whichspace the concrete is later poured. The channels lock over the heads ofthe webs and provide strips of metal or plastic to receive connectorssuch as nails, staples, etc. for securing whichever form of siding isdesired on the outer wall of the building, or for securing panels or thelike on the inside of the wall when the FIG. 10-14 embodiment is used inthe inner surface of the concrete wall.

After each panel is slid into place between the wall forms, conventionalties 16 (shown in FIG. 1) are connected to the wall forms at the edge ofthe panel. The wedges 23 (shown in FIG. 1) are inserted into theinstalled panel, and extend into the edge of the next panel when thelatter is slid into place.

As shown in FIGS. 13-14 outer insulation panels 22 a may be used incombination with the inner insulation panels 22, or it will be readilyunderstood that panels 22 a may be used to insulate only the outer wallof the concrete wall.

When both the inner and outer walls are to be insulated, each of panels22 and 22 a are first provided with webs as described above. The pair ofspaced apart panels are then slid between the wall forms, as describedabove with respect to only panel 22 a, so as to form the doubleinsulated wall as shown in FIG. 13, the webs being next to each otherand overlapping as shown in FIG. 14. It will also be understood that aplurality of outer panels 22 a may be stacked vertically so as toinsulate more than one story of a building, and they may be used belowgrade with a waterproofing coating or membrane between the earth and theinsulation panel. With the double sided insulation, R values as high as50 may be obtained, and when only the outer surface of the wall is to beinsulated, it is only necessary to eliminate panel 22 and use shorterties.

With the simple elements and method of construction as described above,one or both sides of the concrete wall may be insulated without a secondstep of securing insulation after the concrete is poured and hardened.Thus, the total structure is both low in cost and can be installed muchmore rapidly and efficiently than previously known apparatus or methodsin the concrete wall industry.

From the foregoing description of two preferred embodiments it will beapparent that numerous variations in the details will be readilyapparent to those skilled in the art. Accordingly, it will be understoodthat the foregoing description is purely illustrative of the principlesof the invention, and that the invention is not intended to be limitedother than as expressly set forth in the claims interpreted under thedoctrine of equivalents.

1. A system for insulating a concrete wall between two spaced: apart wall forms while the concrete wall is being poured comprising: (a) at least one panel of thermal insulation material in said space; (b) a plurality of elements extending through at least a portion of the thickness of said insulation panel, said elements having head portions; and (c) at least one connecting means extending vertically and over said plurality of elements.
 2. The apparatus of claim 1 wherein said at least one connecting means engages said wall form.
 3. The apparatus of claim 1 wherein said at least one connecting means engages said insulation panel.
 4. The apparatus of claim 1 wherein said elements comprise webs and said connecting means comprise at least one channel having a U-shaped cross-section.
 5. The apparatus of claim 4 wherein said at least one panel with said webs and channels is positioned so as to be in engagement with a surface of the concrete wall after the concrete wall is poured.
 6. The apparatus of claim 4 wherein said at least one panel with said webs and channels is positioned so as to be in engagement with the inner surface of the concrete wall after the concrete wall is poured.
 7. The apparatus of claim 4 wherein said at least one panel with said webs and channels is positioned so as to be in engagement with both the outer and inner surfaces of the concrete wall after the concrete wall is poured.
 8. An apparatus for insulating both sides of a concrete wall while it is being formed comprising: (a) spaced apart layers of insulation material positioned between the wall forms and in engagement with the inner surfaces of the wall forms; (b) a plurality of elements with apertures extending through each of said spaced apart layers of insulation and into the space between the wall forms and extending in opposite directions; and (c) said elements having enlarged portions at least partially embedded in the outer surface of each of said insulation layers.
 9. The apparatus of claim 8 including vertically extending means in engagement with said elements for forming a vertical surface for receiving a plurality of connector means.
 10. The apparatus of claim 8 including vertically extending channel means surrounding said enlarged portions.
 11. An apparatus for insulating at least one side of a concrete wall while said wall is being poured into the space between wall forms comprising; (a) at least one horizontally extending footer below grade; (b) at least one insulation panel extending vertically upward from said footer; (c) a plurality of webs extending horizontally through said at least one insulation panel into said space; and (d) vertically extending members engaging said webs.
 12. The apparatus of claim 11 wherein said webs include head portions and said vertically extending members engage said head potions.
 13. The apparatus of claim 11 wherein said one side of said concrete wall comprises the inside of said wall.
 14. The apparatus of claim 11 wherein said one side of said concrete wall comprises the outer of said wall.
 15. The apparatus of claim 11 wherein said at least one side of said concrete wall comprises the inside and outer of said wall.
 16. A method of insulating a concrete wall between two spaced apart wall forms forming a space into which concrete is to be poured comprising; (a) forming at least one panel of insulation; (b) forming apertures in said at least one panel; (c) inserting horizontally extending elements into said apertures such that said elements protrude outwardly of said panel; (d) sliding said at least one panel with said elements into the space between said wall forms and into engagement with at least one of said wall forms.
 17. The method of claim 16 wherein said at least one panel comprises first and second panels spaced apart.
 18. The method of claim 16 including the step of connecting said wall forms together by horizontally extending tie means after said at least one panel is slid between said wall forms, and subsequently sliding additional panels into said space and installing additional tie means.
 19. A method of forming insulation layers for use in insulating a concrete wall comprising: (a) providing a block of insulation material; (b) cutting apertures through said entire block; (c) cutting said block into a plurality of layers with each layer having said apertures; (d) inserting horizontally extending elements through said apertures in at least one of said layers so as to form portions of said elements extending beyond the thickness of said at least one layer.
 20. The method of claim 19 including the further step of surrounding said elements with concrete.
 21. The method of claim 19 wherein the step of inserting said elements through said insulation layer includes the steps of leaving a portion of said elements exposed on the side of insertion into said layers.
 22. The method of claim 21 including the additional step of securing elongated members to said extending portions of said elements.
 23. A thermal insulating apparatus comprising: (a) at least one thermal insulation panel; (b) a plurality of elongated elements extending through at least a portion of the thickness of said at least one insulation panel, said elements having head portions; and (c) means for engaging said heads and securing said elements together.
 24. The thermal insulating panel of claim 23 wherein each of said elongated elements include at least one aperture means for permitting concrete to flow through said elongated elements from a first side to the second side of said elements.
 25. The thermal insulating panel of claim 23 wherein said means for engaging said head comprise channels having U-shaped cross-sections. 